Liquid proportioning apparatus



Oct. 1, 1968 P. B. BLOOD 3,403,821

LIQUID FROPORTIONING APPARATUS Filed Dec. 20, 1965 2 SheetsSheet 1 g WWW Ill J e0 INVENTOR.

m B BLOOD BY MALLINCKRODT a MALLINCKRODT ATTQRNEYS Oct. 1, 1968 P. B. BLOOD LIQUID PROPORTIONING APPARATUS Filed Dec. 20, 1965 FIG. 3

2 Sheets-Sheet 2 FIG. 4 65 INVENTOR.

PAUL B. BLOOD BY MALLINCKRODT 8| MALLINCKRODT ATTORNEYS United States Patent 3,403,821 LIQUID PROPORTIONING APPARATUS Paul B. Blood, P.0. Box 39, Bountiful, Utah 84010 Filed Dec. 20, 1965, Ser. No. 514,878 3 Claims. (Cl. 222-63) ABSTRACT OF THE DISCLOSURE Liquid proportioning apparatus for delivering, under pressure, a liquid to which has been added a predetermined quantity of an additive liquid or liquids. The apparatus comprises a multiple acting, reciprocating, main pump connected in a liquid flow system for pumping a primary liquid from a source of same to a pressure discharge outlet, and a metering pump connected in the system for pumping predetermined quantities of an additive liquid or liquids from a source of same to discharge into the primary liquid. The system is so arranged that, on each discharge stroke of the main pump, the metering pump is powered by pressure discharge from the main pump. The main pump is preferably controlled by pressure differences in the system caused by opening and closing the pressure discharge outlet.

This invention relates to apparatus for adding a liquid to another liquid in predetermined volumetric ratio and for discharging the mixed liquids in a high-pressure stream for cleansing, spraying, and other uses.

More particularly this invention is concerned with apparatus for supplying streams of liquid to which another liquid has been added, and especially with such an apparatus capable of developing a high pressure flow stream for industrial cleaning or spraying operations and with means for continuously feeding a cleaning detergent, insecticide, pesticide or other additive to a primary liquid such as 'water in an amount proportionate to the high pressure volume discharged.

Apparatus of this type is frequently used to clean dirt, oils, etc. from automobiles, but it can also be employed in industrial plants, and in other commercial establishments to clean structures and equipment, or it can be used for many other cleaning purposes. In extermination Spraying, and in other operations as well, it is desirable that the spray be ejected from a nozzle at very high pressure so that the liquid made up of primary liquid and an additive will be atomized as it expands after passing through the nozzle orifice.

It is often very important that additive be supplied to the primary liquid in a continuous exact proportion. This is because although a particular amount of additive may be required to perform a particular job in a satisfactory manner, no more additive than that required should be added if the operation is to be done as economically as possible. It is also desirable that the flow stream made up of primary and additive liquids be instantly available for use, with no significant time lag between the demand and the discharge from a distributing nozzle.

A principal object of the present invention is to provide apparatus that will develop a high pressure fiow stream of a primary liquid that can be used as a cutting tool in cleaning operations and as an atomizer in spraying operations and to which an additive can be continuously and positively injected in a predetermined amount proportionate to the volume of high pressure stream flow. Other objects are to provide such apparatus that. is simple and relatively easy to construct, that is extremely durable and reliable, that has a metering pump that can be easily disassembled and reassembled to vary the flow characteristics of the additive liquid, as desired, and that 3,403,821 Patented Oct. 1, 1968 "ice will, under all normal use conditions, provide substantially instantaneous discharge from. a distributing nozzle.

There is shown in the accompanying drawings a specific embodiment of the invention representing what is presently regarded as the best mode of carrying out the generic concepts in actual practice. From the detailed description of this presently preferred form of the invention, other more specific objects and features will become apparent.

In the drawings:

FIG. 1 illustrates in semischematic form the novel apparatus of the invention and the flow paths of the main flow stream and additive liquids;

FIG. 2 is an enlarged vertical section taken on the line 22 of FIG. 1, through the metering pump of the invention;

FIG. 3, a similar view through the pressure control assembly, taken on the line 3-3 of FIG. 1; and

FIG. 4, an enlarged fragmentary horizontal section through the nozzle, taken on the line 4--4 of FIG. 1.

Referring now to the drawings:

In the illustrated preferred embodiment a main pump 10, shown powered by a motor 11, is driven through a chain 12 interconnecting a sprocket on the motor and sprocket 13 on the pump. The pump can be of any conventional, multiple actin high pressure, reciprocating type, and among others a model A04-6 manufactured by F. E. Myers Pump Co. has been found satisfactory.

The intake line 14 of pump 10 can be connected to any desired supply of water or other primary liquid, the only requirement being that the supply be adequate to maintain a continuous feed to the pump as oppositely acting pistons 15 and 16 therein are reciprocated. The primary liquid is supplied to cylinders 17 and 18 of main pump 10 through intake pasages 19 and 20, respectively. Check valve 21 in passage 19 and check valve 22 in passage 20 prevent reverse flow through the passages during the discharge strokes of the pistons 15 and 16. The water is discharged from cylinders 17 and 18 through lines 23 and 24 respectively that connect with a main discharge conduit 25 having a gun-type nozzle 26 on its free end. Check valve 27 in line 23 and check valve 28 in line 24 prevent reverse flow from conduit 25 through lines 23 and 24 during the intake stroke of the pistons 15 and 16, respectively.

During the discharge stroke of piston 15 and the simultaneous intake stroke of piston 16 primary liquid is forced through a small line 29 to a chamber 30 at one end of a metering pump, shown geenrally at 31. At the same time primary liquid in a chamber 32 at the other end of the metering pump is forced through a line 33 and into the cylinder 18 of pump 10.

The pressurized liquid forced through line 29 and into chamber 30 acts on a piston 34 to drive it within a sleeve 35. This forces additive liquid at the other side of the piston from a chamber 36 within the sleeve, through a check valve 37 and line 38 into a line 39 that connects with intake line 14 to the main pump. As will be explained, the additive liquid in chamber 36 is supplied from a reservoir 40.

Piston 34 is connected to another piston 41 in a sleeve 42 by a rod 43 that passes through a. partition 44 separat ing sleeves 35 and 42 within the metering pump 31. Thus, as pressurized liquid acts on piston 34 to move it within sleeve 35, piston 41 is moved to force liquid from the chamber 32 at one side of the piston 41, through the line 33 and into cylinder 18 of pump 10, while the piston 16 is On its intake stroke. At the same time additive fluid from reservoir 40 is drawn into a chamber 45 at the other side of piston 41 through lines 46 and 47 and check valve 48.

As the direction of travel of pistons 15 and 16 is reversed, so that piston 15 is in its intake stroke and piston 16 is in its discharge stroke, pressurized liquid is supplied to chamber 32 through line 33. The additive present in chamber 45 at the other side of piston 41 is then expelled through a check valve 49 and a line 50, into line 39 and the intake line 14 of the main pump. Simultaneously therewith, the liquid in chamber 30 is forced by piston 34 through line 29 and into cylinder 17 of the main pump, and additive is again drawn into chamber 36 at the other side of piston 34, through lines 46 and 51 and check valve 52.

A control valve 53 in line 46 has one setting allowing additive to flow from reservoir 40 to line 46 and another setting wherein the flow is between a line 54 and the line 46. Control valve 53 can be either manually or automatically operated, but preferably will be solenoid actuated and operated by a control button, not, shown, but located, as desired, either on the machine or remotely thereof. Line 54 can be connected to the primary liquid or to another additive liquid, but the liquid passed therethrough can also be passed through the metering pump 31.

Sleeves 35 and 42 are respectively tightly fitted in the opposite ends of the bore 55 of a housing 56, with the partition or bushing 44 positioned between them. Bushing 44 has a bore 58 therethrough dimensioned to provide a close fit for rod 43, so that the rod is freely slidable therethrough. Piston 34 is then sealingly but slidably positioned within sleeve 35 and piston 41 is similarly positioned within sleeve 42. The pistons are threaded onto opposite ends of rod 43 and by turning them onto or backing them off the rod their stroke can be adjusted. Naturally, this will vary the volume of additive discharged from the metering pump during each stroke of the pistons. For many purposes this piston and connecting rod arrangement provides all of the adjustment for length of stroke of the pistons that is necessary and it allows a trained person to easily set the stroke length while persons without knowledge of the pump details are not likely to vary the setting.

Elbows 59 and 60 are respectively threaded into the opposite ends of bore 58 and hold the sleeves 35 and 42 in position. Elbow 59 also provides support means for a threaded post 61 that is adjustably threaded through the wall of elbow and that extends into the chamber 32 to serve as a limit stop for the piston 40. By releasing lock nuts 52 that are tightened against the elbow it is a simple matter for a user to turn the threaded post into or out of chamber 32, thereby further varying the allowable length of stroke of the pistons. To change the size of the rod 43 with respect to the pistons 34 and 42, and thereby change the pressure under which the additive liquid is injected into the main stream it is only necessary to remove one of the elbows, take out the adjacent sleeve, the bushing, the pistons, and rod 43 and to then insert new pistons interconnected by a different size rod. The bushing 44 must, of course, be dimensioned to closely surround the new rod. The removed sleeve and elbow are replaced and the metering pump is again ready for operation.

Thus, it is a simple matter to change the stroke length of the pistons 34 and 41, and, therefore, the volume of additive injected into the main flow stream during each stroke of the metering pump pistons. It is also a simple matter to change the size of the rod relative to the pistons, to thereby vary the pressure at which the additive is fed from the metering pump to the main fiow stream and thus insuring that the additive liquid from the metering pump is at a higher pressure than the main flow stream into which it is fed.

In the preferred construction the pistons 34 and 41 are constructed of a plastic such as Delrin or of another long wearing material having good lubricity, that will not easily deform and that will form a tight seal with the sleeves. The threaded connection between the rod 43 and the pistons, in addition to providing a stroke adjustment 4 means, facilitates easy assembly and disassembly and the positioning of bushing 44.

The sleeves 35 and 42 are preferably made of stainless steel and the bushing or partition 44 is of bearing brass. The pistons fit tightly within the sleeves to preclude the necessity for using seals therebetween. A seal is not required between the bore 58 of bushing 44 and the rod 43 it surrounds since any slight seepage through the bore will not significantly affect the operation of the metering pump.

In operation, pivoted trigger 63 of gun nozzle 26 is squeezed towards the handle 64. This opens a valve 65 that has its rod 65a pivotally connected to the trigger, against the biasing effect of spring 66 positioned between gun-nozzle housing 67 and a plate 68 on rod 65a, and allows liquid in line 25 to flow out the orifice 69. As the pressure in line 25 is reduced in response to the opening of valve 65 a piston 70 in a bore extending through a pressure switch housing 71 is biased into the housing by a spring plate 72 that has one of its ends fixed to the switch actuator housing. Continued movement of the piston 70 will allow an adjustable set-screw 73 that is threaded through the spring plate 72 and held in postion by a lock nut 74 to engage and close a normally spring biased open contact 75 of a switch 76. This completes an electrical circuit through lines 77 and 78 to start the motor 11 that drives pump 10. This drives pistons 15 and 16 to continuously supply primary liquid from inlet line 14, under pressure, to line 25. At the same time a portion of the pressurized primary liquid is forced through either line 29 or line 33 to one end of the metering pump to drive the pistons therein and to normally eject additive liquid from the metering pump through either line 38 or line 50 and line 39 into the inlet line 14. Primary liquid at the other end of the metering pump is then forced back into a cylinder of the main pump and charge of additive from reservoir 40 is drawn into the metering pump. The additive injected into intake line 14 is thoroughly mixed with the primary liquid as they are drawn into and ejected from pump 10.

The proportion of additive liquid to primary liquid discharged through line 25, will be dependent on, among other factors, the length of stroke of the pistons in the metering pump and the effective area of the rod connected surfaces of the pistons, and these can be varied as previously described. The pressure at which the additive liquid can be injected depends on, among other factors, the relative sizes of the effective areas of the surfaces of the pistons 34 and 41 of the metering pump and this pressure can be varied by changing the size of the rod 43 relative to the pistons, to thereby change the effective differential area. Thus, the volume of additive liquid supplied to the primary liquid can be set, as desired, and the pressure at which it is supplied can be regulated to insure complete mixing.

If it is desired to supply only primary liquid through the discharge line valve 53 can be operated to cut off flow into line 46 from reservoir 40 and then be operated to allow fiow of primary liquid from line 54 into line 46. With the valve in the latter position, primary liquid will be passed through the metering pump, thereby cleaning the pump before it is forced into the main flow stream.

To shut down operation of the apparatus it is only necessary to release trigger 63, thus allowing valve 65 to close on its seat. The resultant back pressure in line 25 acts on piston 70 to push it against spring plate 72. Set screw 73 is moved away from contact 75 and the contact is moved to its normally open position, breaking the operating circuit for motor 11.

Even while operation of the apparatus is stopped the system remains completely primed and liquid is ready for almost instantaneous discharge from gun-nozzle 26 after the trigger 63 is squeezed in response to such a demand.

Whereas there is here illustrated and specifically described a certain preferred construction of apparatus which is presently regarded as the best mode of carrying out the invention, it should be understood that various changes can be made and other constructions adopted without departing from the inventive subject matter particularly pointed out and claimed herebelow.

I claim: 1. A liquid proportioning system, comprising a multiple acting, reciproctaing, main pump for pumping a primary liquid; a metering pump for pumping an additive liquid, said metering pump including a housing defining pumping chambers, a pair of oppositely acting pistons in respective pumping chambers of said housing, means rigidly interconnecting said pistons for simultaneous opposed operation, and means separating said pumping chambers and sealing otf communication therebetween; a reservoir for the additive liquid; conduit means interconnecting said main pump and said metering pump, so that, on each discharge stroke of said main pump, said metering pump is powered by liquid from the main pump to discharge additive liquid into the primary liquid, said conduit means including conduits interconnecting a set of pumping chambers of the main pump with a set of pumping chambers of the metering pump; conduits interconnecting said reservoir and an opposed set of pumping chambers of the metering pump, and conduits interconnecting said opposed set of pumping chambers with the intake of the main pump; valve means controlling flow through the metering pump, said valve means comprising a check valve in each of the conduits communicating with said opposed set of pumping chambers to prevent reverse flow from the metering pump to the rservoir and from the main pump to the metering pump; a discharge line for liquid discharged from the system;

and a control means for controlling flow from the main pump and the metering pump, so as to maintain the system primed at all times, said control means comprising a valve in said discharge line, and an electrical circuit, including a motor for driving the main pump and a normally closed switch arranged to be biased open when pressure in excess of normal operating pressure builds up in said discharge line, and means responsive to the said excess pressure in said discharge line for opening said switch in response to closing of said valve. 2. A liquid proportioning system, comprising a multiple acting, reciprocating, main pump for pumping a primary liquid;

a metering pump for pumping an additive liquid, said metering pump including a housing defining pumping chambers, a pair of oppositely acting pistons in respective pumping chambers of said housing, means rigidly interconnecting said pistons for simultaneous opposed operation, and means separating said pumping chambers and sealing off communication therebetween; a reservoir for the additive liquid; conduit means interconnecting said main pump and said metering pump, so that, on each discharge stroke of said main pump, said metering pump is powered by liquid from the main pump to discharge additive liquid into the primary liquid, said conduit means including conduits interconnecting a set of pumping chambers of the main pump with a set of pumping chambers of the metering pump; conduits interconnecting said reesrvoir and an opposed set of pumping chambers of the metering pump, and conduits interconnecting said opposed set of pumping chambers with the intake of the main pump; valve means controlling fiow through the metering pump, said valve means comprising a check valve in each of the conduits communicating with said opposed set of pumping chambers to prevent reverse flow from metering pump to the reservoir and from the main pump to the metering pump; a discharge line for liquid discharged from the system;

and a control means for controlling flow from the main pump and the metering pump. 3. A liquid proportioning system according to claim 2, wherein the housing of the metering pump has a rectilinear bore therethrough for providing the pumping chambers; wherein the separating and sealing means comprise a partition; wherein the pistons are slidably fitted in said pumping chambers, respectively; and wherein the means rigidly interconnecting the pistons is a rod slidably passed through the partition.

References Cited UNITED STATES PATENTS 417,046 12/ 1889 Kendrick 13799 X 1,182,721 5/1916 Traudt 137-99 2,306,601 12/1942 Harrington 137--99 2,336,446 12/ 1943 Tucker et a1. 10352 2,442,916 6/1948 Buchanan 103-52 X 2,634,885 4/ 1953 North 222-63 2,736,466 2/ 1956 Rodth 222334 X 3,097,764 7/1963 Loeser 22263 X ROBERT B. REEVES, Primary Examiner.

KENNETH N. LEIMER, Assistant Examiner. 

